Fibromyalgia, Hashimoto's, and side effects to Hormones

I've been diagnosed with fibromyalgia and (seems to flare up only when I'm under actue stress for me), Hoshimoto's (which I take Levoxyl for).  

I have a reaction to birth control pills that is strange and I can't find any information on other people having this problem. I've tried many different kinds of oral contracepts and even most recently the Nuvo ring.  I had the exact same side-effects with each and every one.  Although, the Nuvo ring was slightly less severe which is notable since it contains a lower dose of hormones.  

So, here it is, when I take oral contraceptives I feel fine, actually quite well, for about 21-22 hours a day.  But then each evening, I go through a 2-3 hour period of hellish side-effects.  I feel very dizzy, I feel like there's pressure in my head (I feel this is my eyes, nose, and ears), and its like a grid of pain points lights up on my body - I have one in my foot, one in my forearm, one on my upper pectoral, as well as several in my quadrocepts and calves, a few in my back and shoulders.  These feelings are also frequently accompanied by pulsating headache in a specific part of my head, and ringing in my ears.  

I want to know what would be going on chemically in my body that it creates such an intense reaction on such a regular schedule.  And I want to know if anyone else has experienced similar symptoms.